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All of the products reviewed here have been bought with my own money and nobody pays me for the time I spend writing these articles.

If you find any of this stuff useful and/or would like to see RCModelReviews continue to publish material like this then please consider making a small donation towards the operation of the site.

 

My Credentials
So who's doing this reviewing then?

Well I've been building and flying or driving radio controlled models for over 40 years and during that time I like to think I've built up a reasonable amount of knowledge.

I'm also a qualified electronics engineer who has worked in radio frequency, analog, digital systems and software for more than three decades. In fact I designed and built my first RC set back in 1969.

For the past nine years I've also been involved in the design and manufacture of some rather sophisticated engine technology and UAV flight control systems.

So, chances are I've been there, done that and have a huge pile of tee shirts to prove it.

Right now I'm heavily into 3D flying and enjoy all aspects of the RC hobby. I may be old but I don't feel it.

In the Pipeline

Here's just a little bit of what's to come on this site...

RC explained: Demystifying terms such as PCM, PPM dual conversion, single conversion, full-range etc., this feature will explain it all.

Cheap Chinese Engines: Just how good are those cheap Chinese glow and gas engines that sell for half the price of their "brand-name" equivalent? I put several to the test.

Build your own radio gear?: Back in the old days, building your own RC gear was not uncommon and now the arrival of 2.4GHz has made it practical again.

 

Spektrum transmitter

2.4GHz Radio Control Explained

JUST HOW DOES SPREAD SPECTRUM RC REALLY WORK?

If you've got, or you've been thinking of buying, a 2.4GHz spread-spectrum RC set then you'll probably be keen to understand exactly how it works, and hopefully this article will help you do so.

First, a few words about older "narrowband" RC systems...

Traditional narrow-band RC systems on anywhere from 27MHz to 72MHz are fairly easy to understand because they work just like your regular AM or FM radio - sending out a signal that is picked up by the receiver and then sent to the servos.

Unfortunately, just like regular FM broadcast radio, these RC systems require a frequency all to themselves if they're going to avoid interference with each other. What's more, it doesn't take much to disrupt a regular narrow-band signal. A noisy thermostat or electric drill can often cause massive amounts of electrical interference when listening to an AM broadcast and FM isn't always that much better.

But manufacturers of spread spectrum (SS) radio systems are claiming that you need never worry about being shot down by other fliers and that all 2.4GHz systems can get along in harmony, despite apparently using the same frequencies.

So how can that work?

Well to explain this, I'm going to use a series of illustrations that I call "the freeway analogy". Using these diagrams and explanations, I will do my best to convey the complex world of spread spectrum in a form that most people can get their brains around. Of course in doing this I've had to take a few liberties with the details but these are not important.

Which Flavour of Spread Spectrum?

flavors

YES, IT COMES IN DIFFERENT FLAVORS

Before I launch headlong into a detailed explanation, it's worth pointing out that there is more than one flavour of spread-spectrum.

The first and most common type is what we call Direct Sequence Spread Spectrum (DSSS). This involves the transmitter and receiver staying within a fixed part of the 2.4GHz spectrum.

The second type is called Frequency Hopping Spread Spectrum (FHSS) and involves having the transmitter and receiver constantly changing their operating frequency within the alowed limits of the 2.4GHz band.

At the present time, only Futaba and Airtronics use FHSS, the remainder using DSSS.

And right now I can year you asking "which flavor is best?"... to which I have to say... neither and both.

Or, in other words, neither solution is best all the time, there are benefits and drawbacks to both, as you will see. However, it's safe to say that in theory, the Futaba FASST system does give the best of both worlds because it is not only FHSS but also DSSS.

But first, let's see how a traditional "narrowband" FM RC set works on frequencies such as 27, 35, 36, 40, 41 or 72MHz.

Next Page: How do traditional RC systems work?

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The Blog

Updated: 20 Sep 2012
Here's a blog that will keep you informed just what's going on behind the scenes at RC Model Reviews and also tells you a little more about myself.

How compatible are 2.4GHz RC systems?

23 Mar 2010
How come there's no compatibility between different brands of transmitters and receivers? Why can't you use a cheap Chinese receiver with your Futaba FASST radio?

How to get a product reviewed here

4 Mar 2010
Since this has become a very frequently asked question, I've posted this simple guide to getting your product, or a product you're thinking of buying reviewed here at RCModelReviews

How servos work

Useful information on what's inside your servos and how they work.

The Good Oil

Important facts you should know about the oils that are used in our model engine fuels.

Heads-Up: 2.4GHz RC systems tested

How well do five different 2.4GHz systems stack up when hit by interference? The answers are here, with more to come.

Review: Bushnell's $80 Speed Gun

Yes it does work on model airplanes but there are some limitations involved with this bargain-basement radar speed gun.

Review: TowerPro MG995 servo

These are possibly the world's worst servos, find out exactly why you should avoid these boat-anchors at any cost.

Review: SK90

2.4GHz

It's cheap but can it really stack up against other glow engines in the .90 market? Find out in this review.

Review: iMax 9X 2.4GHz radio

How does this cheap 9-channel 2.4GHz radio system perform when compared to big-name systems that can cost two or three times as much? Have the Chinese finally developed a real contender with the iMax 9X?

2.4GHz Explained

Does all this 2.4GHz stuff have your head spinning? 2.4GHz

I've done my best to demystify the whole subject so if you feel like a bit of learning, this is the stuff for you!

Fix That Engine!

How can you tell when your engine needs new bearings? Who has the best prices and service on replacements? Just how do you change them? Get all that information and watch a great video tutorial anyone can follow.

Chinese Servos - How do they stack up?

Servos

The Chinese are now churning out a huge number of very reasonably priced no-name servos. But are they any good?

Baffled by batteries?

Batteries Nicad, NiMH, Li-Ion, LiPoly, LiFePO4, A123... the range of different battery types has never been greater. So how do they differ and what type should you be using?

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